52+15{#blank#}1{#/blank#}15+52            6+2×6{#blank#}2{#/blank#}(6+2)×6

23-3×9{#blank#}3{#/blank#}27-9-9        50-14-16{#blank#}4{#/blank#}50-(14+16)

5×8{#blank#}1{#/blank#}37            45÷5{#blank#}2{#/blank#}48÷6            8×3+5{#blank#}3{#/blank#}29

31{#blank#}4{#/blank#}5×6+3          4×9{#blank#}5{#/blank#}4×8              48÷6{#blank#}6{#/blank#}48÷8

16+80=    72-9=     41-2=    27+63=    50-30=

3×7=      5×4=      9×9=      8×4=    7×6=

2×6=      8×9=      4×4=     3×6=    9×4=

33+8=     52-7=     71-7=     88+10=    64-6=

5×6+5=       8×4-8=    9×3+9=    4×6-4=

8米+15米=（   ）米          1米-50厘米=（   ）厘米

70厘米+30厘米=（   ）米      20分+40分=（   ）小时